1. Field of the Invention
The present invention relates to onboard display devices and systems for displaying the traveling speed, engine speed, and other conditions of the vehicle. The present invention also relates to vehicles in which the onboard display system is installed.
2. Description of the Related Art
New automobile instrument panels, or onboard display devices, have been suggested. They display driver-supporting information, such as navigation images (“secondary images”), as well as the traveling speed, engine speed, and other information on the conditions of the vehicle. See Japanese published patent application 6-195056/1994 (Tokukaihei 6-195056; published on Jul. 15, 1994) and Japanese published patent application 9-123848/1997 (Tokukaihei 9-123848; published on May 13, 1997).
For example, Tokukaihei 6-195056 provides a wide display screen to improve on visibility, road safety, and ease in operation. Monitor images around the vehicle are displayed on the wide screen along with traveling speed, fuel, and other vehicle-related information.
Tokukaihei 9-123848 provides a wide display device through which the driver is presented with necessary information depending on traveling conditions, to allow for comfortable and smooth driving.
Tokukaihei 6-195056 discloses a display device with a screen measuring 160 to 180 mm in width and 80 to 100 mm in height. The patent application also discloses a specific aspect ratio of 16:9 for display screen. The aspect ratio is the width/height ratio of a display area.
However, navigation images are typically displayed at an aspect ratio of 4:3, 15:9, or 16:9. For example, if a 12:9 navigation image, with the least width, is produced on a Tokukaihei 6-195056 display screen (16:9), the remaining part of the screen has a 4:9 aspect ratio. This means that other images will appear vertically elongated.
A speed display device mounted on an instrument panel for a vehicle is expected also to produce other displays including navigation and rearview images.
If a navigation image is produced on the display device disclosed in Tokukaihei 6-195056 at 4:3 (12:9), the remaining 4:9 part of the screen is not large enough to accommodate a round speedometer display.
The speedometer and related displays are more important than, for example, the navigation system in terms of safety. However, when they are displayed side by side on the Tokukaihei 6-195056 display device, the former appear much smaller and more difficult to recognize. This situation will lead to safety and ease-in-operation issues.
As to the Tokukaihei 9-123848 display device, sufficient resolution is available if navigation and other secondary images and vehicle condition images presenting the conditions of the vehicle are switchably displayed. If these images are however displayed at the same time, sufficient resolution is not ensured for each kind of image. The resultant display is hard to recognize for the driver. This will again lead to safety and ease-in-operation issues.